GENIUS! #11: Dan Dugan and the automixer

Genius is often more than one idea or flash of brilliance. Creative and technological greatness can be seen as when a person creates other things or continues to improve the original invention. Dan Dugan had the initial spark that led to the auto mixer, which, forty years later, is still evolving.

Dugan sees himself as an inventor but, unlike John Meyer, who he regards as a genius, one who did not have formal engineering training. The young Dugan made "smelly chemistry experiments" and "played with electricity". He was also interested in the combination of the artistic and the technical. "When I went to the theatre I always wanted to go backstage and see the lighting board," he says.

Dugan went on to work in theatre lighting and sound but audio later took over completely. In 1968 he was the first person in US regional theatre to be called a sound designer. While on a touring production of Hair soon afterwards Dugan began to consider the problem of handling multiple channels at the same time.

"I started working on how to deal with many open mics and what to do with them when they weren't needed," he explains. This led to an adaptive threshold with mic gain adjustment, which he patented in 1974 and demonstrated as the Dugan Music System at the New York AES the same year. This was based on the first practical automatic mixing algorithm but Dugan knew it could go further.

While "tinkering" with the logarithmic level detection of the Music System he decided to see what effect using the sum of all the active input mics as a reference would have. This did away with the need for an external reference and produced the Dugan Speech System, which he patented in 1975. "I almost didn't understand what I had done," he comments. "But when I was writing the patent and had to do the mathematics it turned out to be quite simple. It was a discovery rather than an invention."

Dugan says he has "been mining that vein every since" and feels there is "still a way to go with it". At the age of 71 he expects to be working for "20 more years", so the genius of the automixer burns on.